U.S. Pat. No. 5,435,586 to Smith discloses a gooseneck apparatus for both hauling heavy equipment on a lowboy trailer and towing a disabled vehicle. FIG. 1 is illustrative of this type of apparatus and the gooseneck apparatus is designated by the reference numeral 10. The apparatus includes a gooseneck 1 mounted to a towing vehicle 3. One end of the gooseneck is pivotally mounted at 5 so that the gooseneck can swivel when hauling a trailer but not when towing a disabled vehicle 9 since the gooseneck is locked in the guide frame in the prior art towing configuration.
A hydraulic cylinder assembly 7 is mounted on the vehicle 3 and the assembly is designed to lift the entire gooseneck when towing a disabled vehicle 9. Since the assembly 7 is behind the rear axle/wheels 6 of the hauling vehicle 3, this method of towing causes an upward force at the coupling 5 between the gooseneck 1 and the towing vehicle 3 and a rotation about the rear axle/wheels 6 of the hauling vehicle 3. This causes the front tires 8 to lift off of the ground. Consequently, a counterweight assembly 11 is required at the front of the towing vehicle 3 to keep the desired weight on the front tires of the prime mover.
The gooseneck 1 has a toe 12 that has a dual function. In one mode as the hauling mode, the toe 12 is used and moved in conjunction with the hook 13 to haul a lowboy trailer as is known in the art. In the towing mode, the toe 12 is not moved for towing. Instead, the toe 12 is lowered by movement of the gooseneck 1 due to the cylinder assembly 7 and the end 14 of the toe 12 attached to the underside of the bumper 15 of the disabled vehicle 9. The gooseneck 1 is lifted by reason of the cylinder assembly 7 to raise the front tires 16 of the disabled vehicle 9 off of the ground. The towing vehicle 3 can then tow the disabled vehicle to the appropriate location. In one mode, the end 14 of the toe 12 has a trunnion pin 17 that mates with an appropriate recess in the bumper 15 for towing purposes.
This method of towing has a number of problems as outlined below.                As the trucks get larger and the goosenecks get bigger, a larger counterweight is required. Because the counterweights are getting so large, they are made in two or three pieces to allow for shipping and handling. This requires more handling by mine personnel when going back and forth between the lowboy trailer hauling configuration and towing configuration. And, there's a theoretical limit to how much counterweight can be attached to the front of a towing vehicle.        The existing towing method requires a different set of truck components than a non-towing configuration (the non-towing configuration designed only to haul lowboy trailers) in order to slide the gooseneck forward on the towing vehicle to help reduce the amount of counterweight needed. This adds many components, e.g., subframe, guide frame, slide cylinder lug, slide cylinders, larger apron cylinders (which are analogous to the cylinder assembly 7 in FIG. 1), etc. which adds complexity and the inherent issues that come with that. Because of that, it is a substantial retrofit and cost for a mine to upgrade from non-towing to towing. These towing/hauling configurations and non-towing configurations are well known and a further description of the details of the towing vehicle components is not necessary for understanding of the invention.        The existing method also requires someone under the disabled vehicle relaying signals to another person standing beside the truck that gives directions to the operator in the towing vehicle in order to get the end of the toe 14, which has the trunnion pin 17 lined up correctly. It usually takes several tries “forward and back” and “side to side” to make the connection and it puts the person under the truck in a dangerous situation. This is even more difficult with the electric trucks because they tend to “lurch”, making it tough to get lined up correctly.        There is not a positive connection between the towing vehicle and the disabled vehicle and this is a problem.        There is a limited turning radius in the towing configuration. This is because the rotation point is at the center of the front bumper 15 and a part of the toe 12 can contact the bumper if the turn is too sharp. Also, the operator of the towing vehicle doesn't have a clear view of this area to determine when he is at the maximum turning capability.        